In general, no – you don’t need planning permission for a Velux window. The Planning Portal says that you don’t need to apply for planning permission to install a roof window if the following conditions are met:
- A roof window must not protrude more than 150 millimetres above the existing roof plane No roof window or any other alteration can be higher than the highest part of the roof or stand out above the roof ridge
- Side-facing windows must have obscure glazing to protect privacy of neighbours and, if they open, they must be 1.7 metres above the floor of the room in which they are installed
You don’t need to apply for planning permission for a roof window because they are covered under permitted development rights. However, if you’re a leaseholder or you live in a building where your local authority has made an Article 4 Direction, you will have to apply. Usually, an Article 4 Direction is made when you live in a conservation area where any external home improvements could affect the character and look of the area. Luckily, there are special Velux windows that are designed to be more likely to be accepted by your local planning authority. They’re called conservation windows and, although there’s still no guarantee that they will be accepted, they are designed to look more traditional. Even if you don’t need planning permission for your roof window, you still need to follow any relevant building regulations for your local authority. The most important parts for Velux windows are section J and section L of building regulations, which refer to energy efficiency, thermal insulation and fire protection.